When figuring the variance of the distribution of means based on an estimated population variance, you divide the estimated population variance by __________

Alcohol, barbiturates, and opiates are classified as ______

a. hallucinogens c. stimulants b. catatonics d. depressants

In body language, relaxation is communicated by

a. casual positioning of arms and legs. b. leaning back, if sitting. c. spreading of the arms and legs. d. all of these positions.